Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, covering the read-only and non-destructive nature. The description adds a behavioral nuance by stating 'without sending a message', which clarifies the tool is not a communication action—useful context beyond the annotations, especially given the word 'contact' might suggest messaging. This extra specificity earns a 4.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, front-loaded sentence with zero waste. It presents the primary usage condition first, then the resource, and fits entirely in one line. This is the ideal level of conciseness for a simple tool.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read-only, zero-parameter tool with an output schema, the description is fully complete. It states what the tool returns and when to use it. Since there are no inputs, no behavior beyond read-only is needed, and the output structure is defined by the schema. Nothing an agent would need to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0 parameters and 100% schema coverage (trivially), there is no ambiguity. Per the rubric, 0 params sets a baseline of 4. The description adds no parameter details because none are needed, and it does not contradict the schema. This is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb ('return') and resource ('public contact and profile links'), and explicitly contrasts with sending a message. It clearly differentiates from sibling tools that return experience, projects, publications, or writing content, so an agent can immediately know this is the right tool for contact/profile data.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description opens with an explicit trigger condition ('when an agent needs to return public contact and profile links without sending a message'), giving clear guidance on when to invoke it. It does not explicitly list exclusions or alternative tools, but the context is unambiguous for a zero-parameter tool, and the sibling set makes the alternative obvious.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.